Motor vehicle system devices of the type named at the outset are known from the related art. In principle, they have any desired devices with respect to systems of the motor vehicle, particularly, the drive assembly. The charging device is supposed to be assigned to the drive assembly. It is used for the performance increase of the drive assembly, the drive assembly being able to be, for instance, an internal combustion engine or a fuel cell drive assembly having at least one fuel cell. The charging device has the compressor, which is provided for compressing fluid, particularly gas, and air, for example. The fluid compressed using the charging device is usually supplied to the drive assembly. In this way, the specific power of the drive assembly is able to be clearly increased.
To compress the fluid, the compressor has a compressor runner, which is supported using the bearing, particularly in a housing, or rather, a compressor housing. The bearing is made up of two bearing parts, namely, the first bearing part and the second bearing part. The first bearing part is usually stationary, that is, it does not rotate, while the second bearing part is assigned to the compressor runner, or rather is connected to it in a torsionally rigid manner, that is, to rotate at the same rotational speed. Thus, there is an operative connection between the second bearing part and the compressor runner. For instance, the first bearing part is present as a bearing bush and the second bearing part is present as a shaft area of a shaft, on which the compressor runner is situated in a manner resistant to torsion.
The charging device, or rather the compressor, is usually actuated as a function of an operating state of the drive assembly, the compressor runner, and correspondingly the second bearing part being able to have changing rotational speeds with respect to the first bearing part. The compressor runner may reach very high rotational speeds, in this context, particularly greater than 100,000 r.p.m. This sets very high requirements on the bearing which, for example, is developed as a sliding bearing. In motor vehicle system devices known from the related art, the bearing may be submitted to great wear.